A small portion of the Smith-Mossman Western azalea Garden at Lake Wilderness Arboretum. Photograph by Bob Dunning

The horticultural history of the West Coast is filled with stories of notable plant collectors. Although much has been written in praise of their accomplishments and as a record of their contributions to our gardens, many of their collections fade away and vanish over time. a lucky few are preserved as reservoirs of genetic material for future generations of gardeners and plant enthusiasts. One of the most remarkable examples of preservation is the Smith-Mossman Western Azalea Garden.

Britt Smith and Frank Mossman were passionate about our native, deciduous West Coast azalea (Rhododendron occidentale). Although they were not the first to study the diversity of this species, they were among the most thorough in documenting their observations. They were inspired by the exhaustive work of Leonard Frisbie, a nurseryman from Tacoma, Washington who researched western azaleas during the 1950s; his work represented the only serious study of this azalea since the species was first collected, over ninety years earlier. Smith and Mossman took up Frisbie’s work and strove to show the full extent of diversity within the species. They began their exploration in 1966 and, over the next fifteen years, discovered and documented about 275 unique forms of western azalea along the southern coast of Oregon and in the northern counties of California. Each established vast collections of their discoveries at their home gardens in Washington State.

Smith and Mossman took great care to record their studies in detailed notes. Many of their selections can still be found in the wild by using the information found in those records. When an unusual form caught their eye, they carefully noted the location, bloom time, and flower details, including color, size, number of blossoms per truss, and any unusual or distinctive features. Each unique rhododendron received its own record number; most of these were Smith-Mossman numbers, typically written as “SM #.” Out of this fantastic array of desirable plants, only a handful were assigned cultivar names; one of the most beautiful (SM 232) was given the name ‘Leonard Frisbie’ after the person who had inspired them.

The following brief summary, initially prepared as a script for Britt Smith’s slide presentation on western azaleas, establishes the scope of their team effort:

Rhododendron occidentale is thought to have been first reported in a publication by Sir William Hooker in 1857, and he credits its discovery to a Mr Gray.1 The first seeds were taken to England by Mr William Lobb, who landed in San Francisco in the summer of 1849. The first Rhododendron occidentale bloomed in England in the garden of Mr James Veitch of Exeter in 1857. It is likely that the great fragrance of the species was the reason for its first use in hybridizing. It was crossed with the Ghent azaleas and, after much inbreeding, produced the now well-known Knaphill and Exbury azaleas. Subsequent hybridizing continues in many places, combining and recombining Rhododendron occidentale with Knaphill and Exbury type azaleas, resulting in great beauty and, often, fragrance.

In the United States, Rhododendron occidentale seems to have received little attention until 1952, when Mr Leonard Frisbie began his monumental effort of investigating the species, regarding which he reported in the quarterly publication of the Pacific Rhododendron Society, Rhododendron. His was an effort of dedication with no monetary reward. There were years of research and inquiry in libraries, at universities, and in the field. He made many trips by public conveyance to hunt, inspect, select, and mark outstanding plants. There were winter trips with his friend, Dr Charles S Berry, to collect layers and plants.

The January 1961 issue of Rhododendron, along with some of the plants collected by Mr Frisbie, had come to the attention of Dr Frank Mossman of Vancouver, Washington, who then invited me to join him in continuing Mr Frisbie’s investigation.2

We focused our attention on an area that had been designated by Mr Frisbie as being the most promising. That designation proved correct, and the area soon became known by us as “Occidentale Land.” Roughly, the boundaries are from Coos Bay to Roseburg to Grants Pass to Klamath in Oregon, and on to Eureka in California, and the shoreline of the Pacific Ocean from Eureka to Coos Bay.

Rhododendron occidentale ‘Crescent City Double’ (Sm 28-2), one of a group of double-flowered Western azaleas found near Crescent City, California. Photograph by Britt Smith, courtesy lake Wilderness arboretum

Crescent City is a small town on a beautiful bay near the northwest corner of California, and an inviting place to pause. It soon became the hub of our investigations of Rhododendron occidentale, and a “home away from home” for Dr Mossman and myself. In Crescent City, at the junction of two roads, sits a large pasture where many collections were made, all with the owner’s permission. The plants are poisonous to grazing animals and, seemingly, to everything except mildew and green worms.

Towards the southern end of this area, where most of the exploration was concentrated, is Patrick’s Point and Big Lagoon, California.3

Unfortunately, most of these remarkable selections of western azalea are seldom available today; they can be difficult to root, and seedlings vary greatly from the parent plant. Occasionally, some Smith-Mossman selections can be found at rhododendron specialist nurseries; patience and persistence is the key to finding the best forms available.

In 1997, Britt Smith and his wife Jean decided to sell their home in Kent and move to a smaller, more manageable property. The Kent property was to be subdivided and developed, almost certainly meaning the loss of any plants left in the ground. A last minute deal was struck with the new buyer and developer, allowing for Smith’s azalea collection to be relocated to the Lake Wilderness Arboretum, a public garden in the small town of Maple Valley, southeast of Seattle. A small but dedicated crew set out to move his now fully mature azaleas. Smith’s garden held far more plants than the new arboretum garden could accommodate, so the choicest of the well-documented specimens found their way into the arboretum, while many others were shared with gardeners around the Puget Sound region. In June 2000, the new azalea site was dedicated as the Smith-Mossman Western Azalea Garden, with over 200 selections represented. Frank Mossman also donated part of his collection to the arboretum, further establishing it as the largest collection of Rhododendron occidentale selections in the world.

Now approaching its tenth year, the Smith-Mossman Western Azalea Garden offers a spectacular floral show from late spring into summer. In 2008, the garden was redesigned, with a number of Pacific Northwest natives added to complement the rhododendron collection. A shallow gully, which ran along the edge of the plantings and served as a dumping ground for rocks removed during the initial installation, has now been transformed into a gracefully winding dry gravel streambed. Along with the additional plantings, the entire azalea collection has been plotted out and mapped for future reference. The preservation of these plants became even more important with the passing of Britt Smith in December 2007, and of Frank Mossman in November 2009.

Rhododendron occidentale ‘Stagecoach Frills’, found on a rise at Stagecoach Hill, north of Eureka, California. Photograph by Frank Mossman, courtesy Lake Wilderness Arboretum

A Few of the Best

Britt Smith and Frank Mossman could never agree on their ten best selections of western azalea, but often mentioned some of these personal favorites in published articles:

SM 28, SM 28-1, SM 28-2, SM 28-3 This group represents a small population of double- flowered plants found growing in an area no more than fifty feet in diameter in a location identified as LeMunion’s pasture, near Crescent City, California. Each selection bears ten or more petals per flower. The best of the group, SM 28-2, was eventually named ‘Crescent City Double’.

SM 30 ‘Crescent City Gold’ One of the best “yellows” found in their travels. Each lobe shows an orange yellow coloring. This became a prominent parent of Smith’s breeding program to develop a true, all-yellow Western azalea.

SM 53 Referred to in Smith’s writing as a “freak,” this selection has deeply cut floral lobes, resulting in a ribbon-like appearance for each petal.

SM 148 This is one of the largest flowering forms found. Each individual blossom is about four inches across, with a crease down the center of each lobe, giving a slight twist to the petals.

SM 157 ‘Miniskirt’ One of the smallest discovered, this cultivar’s flowers are only about half-an-inch across. The stamens and styles protrude far beyond the petals, suggesting long legs beneath a miniskirt.

SM 232 ‘Leonard Frisbie’ Considered the best selection ever, they named it after the man who inspired them to seek out Rhododendron occidentale in the wild. This cultivar has large flowers with a highly frilled edge on each lobe and is heavily colored with pink and white.

SM 502 ‘Humboldt Picotee’ The best picotee they found, this cultivar is, however, an unstable plant. A single plant can sport three different variations: the spectacular vivid red-edged picotee flower, a slightly larger flower with a fine line of red on the edge of each petal, or a flower that is almost typical of the species. Branches carrying the best and most dramatic flowers will also have the deepest green foliage marked with dark chocolate-red specks. It is slow and extremely difficult to propagate.

‘Stagecoach Frills’ (no SM #) Large, white-flushed, pink flowers open with a prominent orange yellow flare on the upper lobe. Each lobe is highly frilled, lending a delicate and lacy appearance. It was found near the top of a hill in the area known as Stagecoach Hill.

If You Should Like to Visit . . . The Lake Wilderness Arboretum is located at 22520 SE 248th Street, Maple Valley, WA 98038. Maintained by the Lake Wilderness Arboretum Foundation, the garden’s focus is on Northwest native plants, including the world’s largest collection of western azaleas. For information about membership in the foundation, its education programs, and volunteer opportunities, visitwww.lakewildernessarboretum.orgor call 425/413-2572.

Author’s note: Mr Gray refers to Asa Gray, the botanist who first described Rhododendron occidentale. An herbarium specimen of R. occidentale was most likely collected by George Tradescant Lay, the naturalist on the English sailing ship Blossom, which, under the command of Captain Frederick Beechy, visited the West Coast of North America. The Blossom left England in 1825, returning in 1828. ↩

Author’s note: this area is now Stagecoach Hill Azalea Reserve, approximately twenty miles north of Eureka; it is renowned for its exceptional selections of western azalea, including a frilly flowered one named ‘Stagecoach Frills’. ↩